she's packed up

[stanman]

dont know what i touched but she has started working!!!! wire feed ok gas valve working havn't tried welding yet but i still have no voltage reading between choc bloc blue and any red on the selctor switch! is that right ? i reckon ive got a loose wire somewhere giving a high resistance on a connector somewhere! but i cant understand how that would blow the main 13 amp fuse in the plug?:

 

[stanman]

welding ok same as before thanks everyone for the imput and help, Best Regards, stanman

 

[the snooper]

you wont get a voltage on selector switch until the relay / contactor is in the on position ie trigger squeezed

 

[Sub-arc]

Good stuff. Sorted !

I was typing this when I saw the post but I'll put it up for future ref--
See the 6 alu/shiney pots ? they may store a charge and you may get a belt of them if you touch the screws/connectors. There is a bleed resistor there but better safe etc...

 

[mike 109444]

simple sketch

The fuse may have blown with the surge from the "connect - disconnect" fault.
Ref the blue/red metering it could be wired from brown/red.
See pic for basic metering. As you say chances are you may have loose connection. With power OFF get a very good tourch and look allround that bottom left corner of the m/cbetween the red leads down to the choc block and gently move wire/s looking for the crimped eyelets at ends moving if they are screwed down propperly they won't move. Could be one round the back of the rotary switch! pain to see, use a small mirror. Still the fact that it did come to life does mean most of the m/c must be ok

 

[the snooper]

mike he wont get any voltage from the power switch as it has a contactor inbetween live and the switch

 

[stanman]

i think the old girl needs a good service after all she is 33 years old and has done a ?serious amount of hard work!! does anyone know a reliable service engineer near romford essex, who wont rip me off

 

[the snooper]

to be honest there isnt that much to service only the moving parts, you could give it a clean your self. you could pay your money to get it serviced but if the fault didnt show up then as far as the service guy's concerned there is nothing to fix

 

[mike 109444]

The Snooper. Both my migs have the contactor switching after the rectifier (the DC)!

 

[Mick - Ford Focus]

stanman

Love Reading These "Help Me Fix It - Please" Threads.

I Think Your Now A Fully Qualified Mig Service Engineer, So DIY.

Well Done To Mike Etc For Helping stanman Out.

Mick

 

[the snooper]

The Snooper. Both my migs have the contactor switching after the rectifier (the DC)!

if you zoom in post 4 pic 1 you can see the contactor and the same cable from the power switch conected to it

 

[stanman]

33 year itch

i still have a problem with it not welding properly on the first three positions on the selector, i thought if i could put her into a service engineers hands they would give me a definitive answer as to what the problem is. i manage to get by as she is but this last fault makes me want to get her checked by someone fully qualified to test the various components i.e. the caps and transformer etc. i put a post on here 3 years ago and i thought i had cured the problem but i have just got by welding bodywork on no 3 or 4, whereas when it was new i could weld right down to no 1 and still get proper penetration. i know i cant replace this mig for a newer one that can do the same sort of work without spending a fortune so i think it would be worth more or less reconditioing it so i get another thirty years out of her (ha ha) regards, stanman

 

[the snooper]

chances are its the power selector switch
people have taken them apart and cleaned them

 

[mike 109444]

if you zoom in post 4 pic 1 you can see the contactor and the same cable from the power switch conected to it

Ya but it's one of thoes pic where you just want to move something over a bit to get abetter view It does not help that most oof the wires are (or look) the same colour (could be a bit dusty). Had a similar prob the other day with selector switch and knowing they can turn into a pile of bits I just loosened the stack of switches off a bit, enough to get some contact cleaner spray in and tightened up, all ok. When I've looked at prices for these high current switches in the past, there not cheep!

 

[the snooper]

yeah i think i would try the contact cleaner first if that fails then take apart carefully after all if its shot it shot nothing to lose

 

[stanman]

burn up!

she packed up completely again so gave the selector switch a blast of switch cleaner left it a while and tried again. the switch arced out and the whole of the switch was alight!!! blasted it with fire extinguisher and it went out. m/c started welding again but now she arcs out big time on switch. obviously switch is in trouble on contacts, is it much of a job to clean/service the switch or is it new switch time?

 

[Country Joe]

Well cleaning it didn't give the desired effect, this time. But now that it's been on fire, I think I'd be inclined to change the switch.
CJ

 

[stanman]

Well cleaning it didn't give the desired effect, this time. But now that it's been on fire, I think I'd be inclined to change the switch.
CJ

its still welding though on the high [4-6] range thats whats so annoying! what sort of money are we talking for a new switch?

 

[Country Joe]

That big stacked blue one with all the red wires sprouting out of it?
I've no idea on costs - hopefully someone's just about to tell you it'll just be £3 at RS components or maplins etc.
It might just have some identifying markings on it, and be a known standard of switch, and be readily available - but that'd require 3 strokes of luck in one go!
Otherwise it's a phone call to the makers,(migatronic?) to see how much they want for it, I guess.
If it's loads, I suspect you'll be able to get by with the higher settings until you need to do some thinner stuff, or it ignites again!
Wishing you luck!
CJ

 

[Country Joe]

Hey, all is not lost - see here - 3rd post down!

http://www.mig-welding.co.uk/forum/showthread.php?t=31581

The best part goes like this:-
"even the rotary function switch got changed while I was in there (also from Maplin for about 2 quid)"

Sounding promising, even to a pessimist like myself!

All the Best,
CJ